WO2013007529A1

WO2013007529A1 - Device and method for cleaning sticks for the pasta industry

Info

Publication number: WO2013007529A1
Application number: PCT/EP2012/062552
Authority: WO
Inventors: Lando Landucci
Original assignee: Landucci SRL
Current assignee: Landucci SRL
Priority date: 2011-07-14
Filing date: 2012-06-28
Publication date: 2013-01-17
Anticipated expiration: 2014-01-14
Also published as: ITFI20110137A1

Abstract

The device for washing sticks (C) for the transport of long-cut pasta comprises at least one nozzle (25) generating a jet of dry ice particles directed against the surface of the sticks in the device.

Description

"DEVICE AND METHOD FOR CLEANING STICKS FOR THE PASTA INDUSTRY"

DESCRIPTION

Technical field

The present invention relates to the field of pasta production machinery. More in particular the present invention relates to devices for cleaning the so-called sticks, bars or rods, for supporting, moving and transporting long-cut pasta, such as spaghetti, tagliatelle and the like.

State of the Art

In the food industry, in particular in the production of long-cut pasta such as spaghetti, tagliatelle, bucatini and the like, the pasta exiting from the dies is put onto so-called support and transport sticks that are inserted in a more complex transport system and transport the pasta through the drier, where the pasta is dried at high temperature before being packaged.

These sticks consist practically of aluminum profiles with elongated rectilinear hollow shape, whose cross section has radii of curvature designed to form support surfaces for the pasta. The sticks shall be regularly cleaned to remove the pasta waste deposited on the surfaces in contact with the pasta.

Italian patent n. 1148139 discloses an equipment for automatic cleaning sticks for long-cut pasta, comprising a complex system for automatically moving and washing the sticks by means of adequate counter-rotating cylindrical brushes, between which the sticks pass. This washing system has some aspects that can be further improved, although it is efficient and particularly advantageous thanks to the high degree of automation. In particular, there are some difficulties in completely removing the pasta waste deposited on the stick surface. These wastes are particularly difficult to be removed chiefly because they adhere to the stick surface due to the effect of the temperature in the drier.

There is thus a need to provide an improved stick cleaning system for the pasta industry.

Summary of the Invention

According to the invention a new device is substantially provided for cleaning the sticks for the transport of long-cut pasta, using as a washing means a jet of dry ice particles, i.e. of solid carbon dioxide, in an air flow. The use of dry ice in the form of suspended particles in an air flow for cleaning purposes is well known. In particular, US 2003/0199232 discloses a system for supplying dry ice particles in an air flow towards a cleaning nozzle. WO 2010/078336 discloses a nozzle for generating a sus- pended dry ice particles flow.

However, nowadays this technique has not yet been used for cleaning the sticks used for moving and transporting long-cut pasta. Furthermore, there are neither accessories nor members designed to apply this cleaning system to the sticks used for transporting and moving pasta.

In one embodiment, the device according to the invention comprises a path for advancing the sticks through the device. This advancing path is preferably designed so that the sticks move along the path in a direction substantially parallel to the longitudinal extension of the sticks, contrarily to what occurs in known stick washing machines, for instance in the device disclosed in the above mentioned Italian patent IT 1148139, wherein the sticks are arranged on a pair of parallel chains and moved orthogonally to their own longitudinal extension. The advancing path preferably extends across a washing chamber inside which at least one nozzle is arranged, said nozzle generating a flow of air and suspended dry ice particles. The chamber has preferably an inlet and an outlet passage for the stick, bar or rod to be washed. The shape of the inlet and outlet passages matches at least partly the cross section of the bar, stick or rod, to reduce the amount of dispersed washing suspension.

In particular, the sticks usually have a top substantially cylindrical surface, two substantially planar side surfaces and a bottom substantially cylindrical surface, having a smaller radius of curvature than the top cylindrical surface. The side walls are con- verging from the top to the bottom. In preferred embodiments the inlet and outlet passages of the chamber match the top cylindrical surface and the planar side surfaces of the stick.

The sticks can be inserted into the device manually, although it is possible to produce automatic feeders for inserting the sticks into the washing device.

It is possible to provide a feeder along the stick advancing path through the device for moving the sticks through a washing area. The advancing movement through the washing system can be therefore controlled by the feeder even if the sticks are inserted manually. This allows a better control of the feeding speed and therefore a more efficient washing, avoiding both a too fast passage through the washing area, that could cause an incomplete waste removal, and a too slow passage, that could cause an excessive consumption of energy and dry ice.

The feeder can comprise, for instance, a motorized roller acting on the stick to be washed. The feeder preferably comprises two opposite rollers, one of which is motorized whilst the other can be idle. The stick to be washed can advance through the nip between the two rollers, that are spaced so that both of them press against the opposite side surfaces of the stick. In this way the stick moves forward with a movement parallel to its longitudinal extension. The stick to be washed practically moves along a trajectory that, in the nip defined between the two rollers, is directed orthogonally to the axes of rotation of these rollers. In some embodiments both the rollers can be motorized. This is however not necessary; it can be sufficient to motorize a single roller, whilst the other is mounted idle and acts only as a pressure counter-roller and is driv- en into rotation due to friction. Instead of rollers, the feeder can comprise conveyor belts, for instance a pair of opposite and counter-rotating conveyor belts, between which the stick to be washed advances. Also other types of advancing means or combinations thereof can be provided.

In some embodiments the feeder can comprise two distinct advancing means, spaced from each other long the advancing direction of the sticks to be washed, with the washing nozzle arranged between the two advancing means. For instance, it is possible to provide a first pair of rollers or conveyor belts upstream of the nozzle and a second pair of rollers or conveyor belts downstream of the washing nozzle.

In other embodiments each stick to be washed can be arranged in a fixed washing position and one or more washing nozzle can be moved along the longitudinal extension of the stick. In other embodiments, combined movements of the stick and of the nozzle(s) can be provided.

The sticks are provided, at the ends thereof, with coupling means for coupling to the machinery onto which they are mounted to transport and move the pasta. In particular, at the stick ends L-shaped opposite brackets are usually provided, projecting from the profile of the sticks. In some embodiments, to obtain an effective operation, the washing nozzle can be provided with a movement towards and away with re- spect to the feed trajectory of the sticks to be washed. This movement to and away allows the nozzle to move away from the stick passage area when the bracket of the first end is inserted in the washing area. The nozzle is therefore protected against possible damages resulting from impacts against the stick bracket. Once the bracket has passed the point in which the nozzle is arranged, this latter can be lowered to wash the central body of the stick, i.e. the part of the stick onto which the pasta actually rests. The nozzle is then lifted again when all the longitudinal extension of the useful portion of the stick has been washed, before the second end bracket of the stick arrives in correspondence of the nozzle.

In some embodiments, the movement of the nozzle towards and away with respect to the stick advancing trajectory can be performed manually. However, in some more advanced embodiments of the device according to the invention an automatic actuating member is preferably provided for lifting and lowering the nozzle. This actuating member can be a mechanical member that lifts the nozzle interfering with the bracket projecting from the stick. In other embodiments the actuating member comprises a sensor detecting the stick passage and generating a control signal to control the movement of the nozzle towards and away from the stick advancing trajectory. The sensor can be for instance a photocell mounted at a suitable height, which detects the passage of the stick end bracket.

In other embodiments a sensor may be used, designed to detect the change in a parameter linked with the material of which the sticks are made, in order to generate the control signals to control the movement of the nozzle towards and away from the advancing trajectory of the sticks to be washed. This type of sensor, for instance a ca- pacitive sensor, is more advantageous than the optical sensors, as it is less sensitive to dirt accumulation that in an optical sensor can endanger the correct operation.

The sticks usually have a useful central area forming the rest surface for the pasta, made of a material different than that of the brackets provided for coupling the stick to the pasta advancing machinery. For example, the useful central portion is made of extruded aluminum, whilst the end brackets are made of steel. A capacitive sensor can be used to detect the material change passing from the steel bracket to the aluminum body and vice versa, thus generating a control signal for controlling the movement of the nozzle towards and away from the advancing trajectory or path of the sticks to be washed.

To obtain an effective washing with a limited consumption of air and suspended dry ice particles, according to some embodiments the nozzle is associated with a washing or containment chamber defining a passage for the sticks to be washed. The nozzle generates a flow of air and suspended dry ice particles inside the washing chamber. The washing chamber holds this flow inside a closed or at least partially closed volume, so that the particles can effectively impact against the side surface of the stick passing through the washing chamber thanks to the turbulence generated in- side the washing chamber, reducing at the same time the product dispersion in the surrounding environment or in the inner volume of the device. The washing or containment chamber associated with the nozzle can be formed by the nozzle itself, for instance the nozzle can be shaped so as to form the washing chamber surrounding a containment volume for the flow of air and dry ice, i.e. carbon dioxide in the solid form or in form of powder or suspended particle.

In some embodiments the washing or containment chamber associated with the nozzle has an inner wall approximately in the shape of a solid of revolution, for instance a spherical or ovoid solid. The chamber wall advantageously have at least one slot or opening, through which the stick to be washed moves relative to the nozzle.

In general, the washing chamber has a through opening for the passage of the stick through the washing chamber itself. In some embodiments the entrance and the exit of the through opening have a profile "matching" the stick profile, i.e. the stick cross section, so as to leave a minimum space between the outer surface of the sticks to be washed and the edge of the entrance and exit openings of the washing chamber, effectively limiting the dispersion of air and suspended dry ice particles.

Further advantageous features and embodiments of the device according to the present invention are indicated in the attached claims, which form an integral part of the present description, and will be described in greater detail hereunder with reference to a non-limiting example of embodiment.

The use of dry ice in this particular application has a lot of advantages. First of all, thanks to the flow of air and dry ice particles the pasta residues adhering to the outer surface of the stick can be removed effectively and reliably, even if they adhere to the surface due to the heating in the driers. The dry ice washing prevents liquid from depositing on the sticks. The dry ice sublimates at ambient temperature; therefore the sticks exit from the device completely dry and clean, without the need for subsequent drying operations and without the risk of bacterial growth in non-perfectly dried areas of the stick. Also the need to remove the exhaust washing liquids is avoided.

According to a different aspect the invention relates to a method for washing sticks for the transport of long-cut pasta, comprising the use of a nozzle to generate a flow of air and suspended dry ice particles, wherein the particles interfere with the stick surface to be washed.

Further advantageous characteristics of the method according to the invention are indicated in the attached claims, and will be better described hereunder.

Brief description of the drawings

The present invention will be better understood by means of the description below and the attached drawing, which shows a non- limiting embodiment of the invention. More in particular, in the drawing:

figures 1 and 2 are two outer views of a device according to the invention; figure 3 is a perspective view of the partially opened device;

figure 4 shows a detail of the inner components of the device;

figure 5 is an enlarged detail of the nozzle and of the corresponding containment or washing chamber for containing the air and dry ice particles flow;

figure 6 shows a detail of the nozzle and of part of the washing chamber associated to it, to show the inner conformation of the washing or containment chamber. Detailed description of an embodiment of the invention

Below a particularly simple embodiment of a device according to the invention will be described, wherein the sticks to be washed are inserted manually. Anyway, the concept on which the invention is based can be also embodied in more complex machines with automatic stick feeding. Conveyors can be for instance provided, on which the sticks to be washed are arranged, manually or through a mechanized sys- tern, and which provides to individually insert the sticks one after the other inside the washing device.

With initial reference to figures 1 and 2, in this embodiment the device, indi- cated as a whole with number 1, comprises a base 3, for instance mounted on wheels 5 so as to be transported inside a laboratory or a plant for pasta production in order to put the device 1 in the most adequate area to wash the sticks. Inside the base 3 a generator 7 is arranged for generating a pressurized air flow, inside which there is a dry ice particle suspension. This type of generators are well known for instance from the patent documents cited in the introductory part of the present description.

A duct 9 connects the generator 7 with a washing nozzle, which is arranged inside a housing or container 11 carried by the base 3 and inside which the stick washing components of the device 1 are arranged, described below with reference to fig- ures 3 and following figures.

The container 11 comprises an entrance and an exit for the sticks to be washed. More in particular, number 13 indicates an entrance and number 15 indicates an exit. Figures 1 and 2 show a stick, bar or rod C fed through the device 1. As said, the stick C can be inserted by an operator through the entrance 13 of the container 11 and collected at the opposite end by the same or other operator.

As shown in figures 3 and following, inside the housing 11 a pair of adjacent rollers 17, 19 is arranged. The rollers 17, 19 can have substantially parallel rotation axes. In the illustrated example the rollers have vertical axes, i.e. their axes are orthogonal to the advancing direction of the stick C, this direction extending parallel to the longitudinal extension of the stick passing through the device 1.

As shown in particular in figure 3, in the base 3 of the device 1 a motor 21 is arranged. By means of transmission members, for instance pulleys or gears, this motor can motorize one or the other or both of the rollers 17, 19. The rollers 17, 19 are counter-rotating so that in the nip defined there between the peripheral speeds of the two rollers are substantially the same as regards both modulus and direction. In some embodiments only one of the two rollers 17, 19 is motorized, whilst the other is driven into rotation due to friction. In this case, the motorized roller acts on the stick C moving it along its path, whilst the other roller acts as a rest and rolling surface and is driven into rotation due to friction with the stick C.

The rollers 17, 19 can be made for instance of rubber of limited hardness, so as to be deformed under the effect of the pressure exerted by the stick C passing in the nip defined between the rollers 17, 19. Inside the housing 11 a washing head is arranged, indicated as a whole with reference number 23, inside which a nozzle is arranged supplying a flow of air and suspended dry ice (i.e. solid carbon dioxide) particles. In figure 6 reference number 25 schematically indicates the nozzle in the head 23, whilst reference number 27 indicates as a whole a containment or washing chamber for the air and suspended dry ice flow. The washing chamber 27 can be shaped for instance like a spherical or ovoid solid of revolution.

In this way the flow of air and suspended dry ice particles is contained inside the washing chamber 27 in a limited volume that surrounds a portion of the stick C to be washed that is temporarily placed inside the washing chamber 27. This latter, as it is shown in particular in figures 4 and 5, comprises a passage defined by an entrance opening and an exit opening indicated with 27A and 27B. The shape of the entrance and exit openings 27A, 27B approximately matches with the shape of the cross section of the stick C so that, as shown in particular in figure 5, the free space between the outer surface of the stick C and the entrance and exit openings is limited in order not to disperse the flow of air and suspended dry ice particles.

When the stick C moves across the washing chamber 27 along the passage defined by the entrance and exit openings 27 A, 27B, a portion of the stick is substantially surrounded by the wall of the washing chamber 27. As a result, the dry ice particles suspended in the air flow injected in the washing chamber 27 of the nozzle 25 impact once or more times the outer surface of the stick C that at a given instant is located inside the washing chamber 27, until they sublimate. In this way, advancing the stick C through the machine according to the arrow F, the entire surface of the useful portion of the stick is washed. The speed of the advancing rollers 17 and 19 is set so that each surface portion of the stick C remains inside the washing chamber 27 for a time sufficient completely to remove the residues and dirt from the stick surface. The advancing speed can be adjustable or fixed.

As it is shown in particular in figure 5, the stick C usually has an elongated cross section with a back CD formed by a substantially cylindrical portion defining the pasta rest surface. In use, the back CD is located at the top of the stick, i.e. the stick is placed with the back CD facing upwardly, so that pasta can rest on the back of the stick. From the back CD two side walls, for instance substantially planar walls, indi- cated with CP, extend downward until a lower substantially cylindrical joining area CI connecting the two side walls CP. The plane side walls CP are usually converging downwards, the surface portion CI having a smaller radius of curvature than the stick back CD. The most debris and residues adhere to the back CD of the stick C. Accord- ing to some embodiments, as shown in the drawing, the conformation of the washing chamber 27 and the arrangement of the nozzle 25 inside thereof are such that the stick C passes through the washing chamber 27 with its back CD directly facing the nozzle 25. In this way a stronger cleaning is obtained on the back CD, where the majority of the residues to be removed are located. Furthermore, the shape of the washing cham- ber 27 is such that the flow of air and suspended dry ice particles invests also the side walls CP where dirt and pasta residues, which must be removed, can be located, even if at a lower extent. The height of the washing chamber 27 is usually and preferably greater than the height H of the cross section of the stick C, so that a part of the flow of air and suspended dry ice particles is also directed against the bottom area CI of the stick C.

As shown in particular in figure 1 and 2, the stick C has two ends CE, each of which is provided with a bracket S for coupling with the pasta transport machines (not shown). The brackets S project beyond the back CD of the stick C. When the stick C is inserted in the device 1 it is convenient that the washing chamber 27 with the nozzle 25 is at such a height not to interfere with the passage of the bracket S associated with the end CE that is first inserted in the device 1. Analogously the nozzle 25 and the washing chamber 27 should not interfere with the bracket S associated with the opposite end that exits from the device 1 lastly.

To this end, in a simplified embodiment of the invention, a manual control can be provided, through which the operator controls the lifting of the nozzle when the ends CE and the brackets S of the stick C must pass through the washing area defined by the washing chamber 27. However, to simplify the operator's work and to obtain a more reliable operation of the device, an automatic mechanism is preferably provided for lifting and lowering the washing head 23 together with the nozzle 25 and the washing chamber 27, so as to move the nozzle 25 and the washing chamber 27 towards and away from the stick C. In the embodiment illustrated, to this end the head 23 is connected to an actuator, for instance a cylinder-piston actuator 31. In other embodiments the actuator can be of a different type, for instance an electric motor. In the illustrated example the cylinder-piston actuator 31 has a connection 33 for the head 23 provided with the nozzle 25 and the washing chamber 27. The lifting and lowering movement of the connection 33 and therefore of the head 23 with respect to the fixed part of the device is indicated with f33. By lifting the connection 33 the nozzle 25, and therefore the washing chamber 27, moves away from the stick C, whilst by lowering the connection 33 the nozzle 25 and the washing chamber 27 move towards the stick C. This lifting and lowering movement can be controlled through the signal of a specific sensor arranged in a suitable position inside the housing or container 11, and schematically indicated with 37 in figures 4 and 5. In these figures the sensor 37 is integral with the fixed part of the cylinder-piston actuator 31. The sensor can also be mounted differently. It will be preferably arranged near or in the same position as the washing nozzle 25 and respective washing chamber 27. The sensor 37 can be a capac- itive sensor, which generates a control signal when a change is detected in the physical composition of the metal material of the stick 5.

In fact, the ends CE and the brackets S are usually made of steel, whilst the central body extending between the two ends CE of the stick C is usually made of aluminum. The sensor 37 can be a capacitive sensor designed to detect this change in the chemical composition. In other embodiments it is possible to detect the passage of the brackets S optically or to detect a change in the electrical capacity not due to the change in the metal type but to the shape change between the body and the end of the stick.

The signal generated by the sensor 37 controls the lifting of the head 23, to allow the entrance of the farthest advanced bracket of the stick C, the subsequent low- ering, to allow the washing of the body of the stick C, and then the subsequent lifting, to allow the passage of the trailing bracket S, i.e. of the bracket associated with the second of the two ends CE passing through the device.

In other embodiments, instead of a pair of rollers 17, 19 another feeder can be used, for instance consisting of or comprising one or more conveyor belts, or a com- bination of conveyor belts and rollers. Whilst in the illustrated example the feeder is arranged downstream of the nozzle 25 and the washing chamber 27 associated with it or formed by it, in other embodiments the feeder can be arranged upstream of the nozzle, or it can be produced so as to have two advancing or feeding members both downstream and upstream of the washing area in which there is the nozzle.

In other embodiments, not shown, the nozzle can be provided with a working movement along the longitudinal extension of the stick, which is temporarily held fixed in a washing position.

In the illustrated embodiment only one nozzle is provided, but it is also possible to use two or more nozzles that can be arranged and controlled so as simultaneously to wash the same stick or also different sticks in parallel or in series.

In the illustrated embodiment the stick C to be washed is in horizontal position and is directed so that the longer dimension of its cross section is directed vertically. In other embodiments, not shown, the stick can be arranged oriented by 90° with respect to the position illustrated in the example of the attached figures, i.e. with the longer dimension of its cross section nearly horizontal. It is also possible to have a reciprocal movement between stick and nozzle in vertical direction instead of in a hori- zontal direction.

It is understood that the drawing only shows an example provided by way of a practical arrangement of the invention, which can vary in forms and arrangements without however departing from the scope of the concept underlying the invention. Any reference numbers in the appended claims are provided for the sole purpose of facilitating reading of the claims in the light of the description and the drawing, and do not in any manner limit the scope of protection represented by the claims.

Claims

1. A device for washing sticks for the transport of long-cut pasta, characterized by comprising: a generator for generating a pressurized air flow containing a dry ice particle suspension; a washing chamber defining a passage for said sticks al- lowing the relative movement between said washing chamber and said stick at least in one direction parallel to the stick longitudinal extension; at least one nozzle generating in said washing chamber a flow of air and suspended dry ice particles directed against the surface of the sticks in said device.

2. Device according to claim 1, comprising an advancing path for the sticks across said device.

3. Device according to claim 2, wherein in said advancing path the sticks move in a direction parallel to their longitudinal extension.

4. Device according to one or more of the previous claims, comprising a feeder to move the sticks through the device.

5. Device according to claim 4, wherein said feeder comprises a pair of members for engaging the stick, at least one of which is motorized and between which said sticks are caused to advance.

6. Device according to one or more of the previous claims, wherein said nozzle is provided with a movement towards and away with respect to a feed trajecto- ry of the sticks to be washed.

7. Device according to claim 6, comprising a sensor detecting the passage of the sticks and generating a signal to control the movement of the nozzle towards and away from the stick to be washed.

8. Device according to claim 7, wherein said sensor detects the difference in the material between the central part of the stick and the ends of the stick, causing the nozzle to move downwards in the central area of the stick and to rise in the end areas of the stick to be washed.

9. Device according to one or more of the previous claims, wherein said passage crosses the washing chamber and has an entrance and an exit, the stick mov- ing through said washing chamber passing along said passage.

10. Device according to one or more of the previous claims, wherein said washing chamber has an inner wall approximately in the form of a solid of revolution.

11. Device according to claim one or more of the previous claims, wherein said passage has an entrance and an exit with a profile substantially corresponding to the stick cross section.

12. Device according to one or more of the previous claims, wherein said washing chamber has a height equal to or greater than the maximum transverse dimension of the sticks to be washed.

13. Device according to one or more of the previous claims, wherein said passage is shaped and oriented so that the stick back surface is arranged in front of the nozzle for the air and suspended dry ice flow when the stick passes across said washing chamber.

14. Device according to claim 13, wherein said washing chamber is shaped so as to define a volume for containing a flow of air and suspended dry ice particles adjacent to stick side walls, extending from the back of the stick towards a joining surface opposite to the back of the stick and connecting the side walls.

15. Device according to claim 14, wherein said washing chamber has an extension greater than the height of the cross section of the stick, to generate a flow of air and suspended dry ice particles in the area of said joining surface opposite to the back of the stick.

16. A method for washing the sticks for the transport of long-cut pasta, comprising the steps of:

providing a washing chamber defining a passage for said sticks allowing the relative movement between said washing chamber and said stick at least in one direction parallel to the stick longitudinal extension;

providing at least one nozzle generating in said washing chamber a flow of air and suspended dry ice particles directed against the surface of the sticks;

generating a flow of air and suspended dry ice particles in said washing chamber; moving one with respect to the other a stick to be washed and said washing chamber with said nozzle arranged therein;

investing said stick with said flow of air and dry ice particles.

17. Method according to claim 17, wherein during washing said nozzle is maintained substantially stationary and said stick is moved along a trajectory parallel to the longitudinal extension of said stick across said washing chamber.

18. Method according to claim 17, wherein said stick is moved forward in a single direction to cross said washing chamber where said nozzle is arranged, entering from a side and exiting from the opposite side of said washing chamber.